All language subtitles for nuk231-class06

hello and welcome back to nuke 2 3 1

nuke compositing best practices

this is Victor Perez

and in this class

we are going to discuss

how to blend pre multiplyed images

without destroying

the grainy structure in the soft areas

okay so let's start by presenting the most common

case scenario

which is a premortified CG

to be mixed with a live action image

so as you know

what you are going to do

is to match the grain from the original plate

and apply it to the CG image

okay in this class

we are not going to discuss how to match the grain

what I'm interested here is to understand

how the grain is going to blend in the soft areas

or even in other areas that are not in the alpha

okay so let's start by understanding what is actually

an application of the grain well

let me tell you that applying the grain to an image

is exactly the same as applying a color correction

so this is my CG image

okay so what I'm doing in here is applying grain

and what this grain is actually doing

is randomizing the frequency of those values

so let's understand the concept of frequency

to continue further

so imagine that in here

we have just a gradient okay

it's just a linear gradient

from zero value to value one

in this case

we are not displaying the gradient linearly

because we are applying an s R

G B call or look up to the beware process

okay so if I deactivate that input

known as you can see now

is clearly a gradient from 0 to 1

okay so let's analyze that using a slice 2

okay you can find this is slice 2 on Wikipedia

this has been created by Frank Rooter

so what this is doing is actually analyzing every pixel

below this yellow line

and is putting the

x coordinates as the special coordinates

so left in here is left to the x

and right here is the right of the x axis okay

while the y axis is representing 0

and the top is representing 1

so this side is normalized

okay so the higher is the value

the higher in position of

why is going to be the pixel represented in this line

okay as you can see clearly

this is a linear ramp okay

so what if I apply the grain okay

let's have a look

well as you can see

the overall ramp is still there

what is actually happening is

every pixel below the line

is now getting a randomization because of the grain

okay so in here

as you can see

you are finding tiny directions up and down

on every single pixel of the RAM

so if I go to the grain amount

and I increase the amount

what I'm doing is adding more contrast

from the highest to the lowest part of the grain

okay so I'm going to reset that to 1

and that is the amplitude of the frequency

but actually

the frequency is

the change that you are getting

from one point of the curve to another

so in here the frequency is quite high

but if I apply a blur

for instance

see that now

you can see

this is like a wave now okay

if I remove the blur

you are going to see like

the values are going up and down

up and down

up and down

without the shape of the wave

as before okay

even sometimes

you can finding here

but have a look at this

happening to the actual image

see the more I increasing

the blur

the value in here

of that randomization is being lost okay

because the blur is actually a high frequency filter

okay but have a look at the ramp

before and after the process

see the RAM is actually the same

well quite close okay

but it's not changing

that is because the grain is not actually changing

the predominant colour of the image

and that is supposed to be like that

if you are changing the colour of an image

because of the grain

then you are in trouble okay

so the grain is actually creating a

Saildo randomization

what I mean with Saildo randomization

is because in computer

you cannot create fully randomize

like the chaos okay

you are creating a pattern

that is looking like a randomization

and this is very important

because sometimes we are going to need to get

the exact randomization

from this note

and from another note

that we are going to see later in this class

okay so I'm going to delete this blur

so you know now that this is just a color correction

so one of the main rules of compositing is

every time you are applying a color correction

to promote applied image

you always have to apply the color correction on

in an unpremorted state okay

so we am pre multiply the image as return with the srgb

then we apply the grain

okay and then we pre multiply the image again okay

so that way

we are preserving every constant uh

grain in every pixel

even when we are getting semi transparent areas

okay well sometimes you can find that notes

like the grain in here

grain have this

apply only through alpha

what this mean is quite similar to the ampromode

ampromode then after the grain

but it's not exactly the same as

it's not the same to use a mask for a color correction

or to use the alpha in the unpremot obligation

and then premot obligation okay

but for the green

this rule has 13 exceptions

because when you are actually getting

the semi transparent areas

what you are doing

is mixing the grain from the original plate

okay the grain in there

with the grain on your CG

and you know

green plus grain

is not equals twice the grain

but it's actually the other way around

when you are mixing grain

you're getting actually less grain

so let me show you here

for instance this rum

which is exactly the same as before I use

yes another note

but this is

this lies too

as before now

is way clear

that you are having randomization

as you can see

okay and here

is the same

but have a look what's happening when I'm

averaging this and this grain

and notice that they both have a different seed

so they are actually the same pattern of the grain

but in different moments

okay so they are not at the same randomization time

okay so if I average those

and I have a look at that

have a look at this curve

see

it's clear in here

when I deactivate the average

the grain expands

but you don't need to have this

is licensed to notice it

you can just go here

and notice that when I am activating the average

the grain seems to slightly disappear

um this is actually one of the tricks

to create a plate without the grain

you just blends the plate if the plate is not moving

so you are going to get everything

with all the frequencies

of the grain just being average

so they are going to disappear at the end of the day

okay so I put another example in here with this

using four grains and see

the more you are going to to add to the average

the more you are going to restore the original shape

of the rump

okay so the frequencies are fighting against each other

okay so this is the problem of mixing the grain

so that's why I'm going to spend this glass

just to show you how is the right way

or the right ways of creating the grain

when you are applying mainly soft patches

okay so in here

if I apply the alpha instead of the primotification

the result is going to be quite close

still not the same well

sometimes is gonna work this way with the amprimote

and then the promote

so the classic color correction amprimote application

and then sometimes you are going to find

that is going to be better just to apply a mask

in this case

if I want to create the same effect

of the primo application set with the Alpha

I'm going to use a shuffle

in here I'm going to call the postage stamp

and now I'm going to put

for the sake of visualizing everything

this in the alpha

okay so this is the alpha

and now I'm going to deactivate that

because I don't want to apply twice the same effect

and now I'm going to call

the key mix

okay so I'm going to apply this on the sides

then this on the other side

because I want to have before the grain

and after the grain

okay so here you are

and now the mask

okay and this

is the mask that is dealing with that

so I'm going to invert the mask okay

so now I'm applying the grain just through the alpha

and why I'm spending that much with the alpha

or the Primo duplication

have a look what's happening

when I'm not applying any kind of limit to the alpha

or to the area of interest

so if you go to the original

and now everything

the limiters have been deactivated

if I rising here the gamma

you will see that the grain has been double

see and this is an error

because you are touching the background plate

and remember

one of the golden rules is never to touch

the background plate if you don't need it

okay so this is adding just an issue

so that's why we're going to use this

that is going to limit

using the alpha masking or the amp multiply

okay and you will find that is quite similar

the difference is

you can play a beat with the density of the alpha

if you are using the key mix option

what I mean is in here

I can place a great

and I'm going to use just the alpha channel

and then with the gamma

I can increase or decrease

and you will notice that in here

in this area that is coming through the window

you're going to apply more or less

okay so the question is

when you need to apply more or less grain

through semi transparency or using the soft edges

then you can use this Chemix option okay

yes to apply the grain

but this is the easiest example

because of course

in here we have the semi transparency

already baked in the alpha

but what happened when that

semi transparency is not reflected in the alpha channel

and is it possible

of course it is

because you can get volumetic light

or incandin sense

or kind of a glowy light from your CG

and that is not going to be reflected in the alpha

because that is going to be at

to the resulting image at the end

so remember that the other whatever is not in the

in the alpha is just going to be like a plus operation

okay so I prepare for you in here

this option

okay which is

let me deactivate the set of the grain for a sec

so you can see the result without the grain

so what happens

for instance

if I get those lens flares in there

so if you have a look at the CG

the Alpha is exactly the same

because those lens flares are not solid

are just light to be at on top

in this case

for the sake of this example

I yet the flares over the CG branch of my compositing

you can add it at the end when everything is mixed

but again you're going to have the same problem

is those flares has no grain

and that is quite unnatural okay

so what if I apply the same trick as before

so using the amp remote and then the grain

and then the promote

here you are

you just kill your flares outside the Alpha okay

and this is why

because the alpha now on after the grain

is going to crop everything that is in black in there

and because your flares have no alpha

they are going to be crop out

so this is a narrow okay

um you can also propose

yeah why don't we use this trick

the one of just as pleating the alpha

then grading the alpha

and then applying the mask for the alpha

just to be dealing with the green

well actually

that is going to be exactly the same problem

because the alpha

he's not covering that area of the flares

so you are going to apply the grain in here

but nothing in there

and probably is not going to be that visible okay

so you are going to have the grain in the solid areas

and no grain in there

that at the end of the day is going to mix

so if you see here

this is exactly the same

you are going to miss the grain in this area

I'm probably

is going to mix with the grain that is already in there

but he's not correct

because you are not adding the same amount

of grain to the flare as is expected

so we need to calculate a work around for that

so for this instance

what we need to get is away of extracting that effect

just to be isolated

and apply the grain just to the effect

and then applying the grain

just for the solid areas of the alpha

okay so we're going to talk about effect separation

okay so in here

what I did is just to create a silly render in here

just put a group

just to make you think what to do

when your barometric lights

or your effects that are not in the alpha

are baked in your render

so if you want to grain that

you need to figure out a way of

getting the effect out of the render okay

another thing to mention is

if you have the

the flares separate in here

you can also propose me ah yeah

why don't we apply the grain just to the flares

and then mix everything together again

well what is actually happening is

you are going to add graining here for the car

and then you're going to add more graining here

for the lens flare

so hmm yeah

probably is gonna work

but is not a good mathematically correct approach

okay so remember

in compositing

everything is cheating

so whatever is going to work is going to work

so nothing to say about that

but if you want to find

a procedural way of getting to a good result

this is how I'm going to show you

okay so I'm going to revert to the flares in there

and in here

what I did is baked everything in one notes

so how can I great the areas beyond the alpha

well in here

what I did is just to create the same effect that the

promote application is going to create with the grain

okay so in here

this is my car with the effect of the amprimote

and then the primote

so I'm just getting rid of the effect

so what if I have this

and I subtract

this so this is what I'm doing actually with this merch

this is an effect extraction

you can use it for many other things okay

so you have in here the minor

so the original image

minus the one with the effect we want to isolate

and here we have the isolation

okay and you can apply this even for the

for this okay

so if you have

this minus that

what you are going to get is just the flares okay

so in case you have effects that are baked in the image

or you need the image to process

for instance

to create a filter kick

or a chromatic aberration or a nail

or any other effects that requires the original image

the way of extrapolating that effect after the process

is using just this

and then how do you mix it

well it's really easy

you put a minus to isolate

then you put a blast to integrate

okay but remember

needs to be done with the original okay

so that is the method for isolating the effect

so in here we got that

so we are going to have

two different processes of the grain

one for the areas of the alpha in here

that is having this grain

and the other

for the areas that are not cover by the alpha

so here what I'm doing is I'm going to apply the grain

but remember that if I apply the grain to everything

I'm going to have grain

even in the areas I don't want the grain to be apply

um because in here there is no alpha

you need to invent the alpha yourself

so if you are using just light

um in this case

the lens flare is just light

what you should do is use aluminum ski

so it's going to be base on the light

so I'm in here

just mixing the original without any grain

and then the grain overall

okay so now

I'm going to deal with it using this luminance key

okay so the luminance key here is just

reflecting all the areas that are being touched by that

luminance okay

so here now

as you can see

I'm applying the grain on those areas

but nothing beyond

okay this is the difference okay

so you can see that there is a tiny Halo

where the green is just decading

so is not going to be at full

well that is normal

and then you need to deal with that

when you get the final image

so here what I'm doing is

I have the green with the premotified areas

then the grain of the non premotified areas altogether

using a plus okay

and then in here you have altogether

and not is that in here you have the grain

see that is going to be a very tiny variation

base is still there

and that is important

so if you want to change that

you can change in the luminance key

the amptitude of that area of the alpha

the problem is the keyer

the note has the limitation

of just setting a black point and a white point

but there is nothing to work in the middle

what is called fall off

or most simply

the gamma between this and that point

so I try not to use the luminance key much

I mean the cure for the luminance key

and I prefer to use my own luminance key setup

so what I did in here is a variation of this

where I can not only use the black and the white point

but also use the gamma here

as a feather fell off

so I'm going to show you how I did it

so this is my original image

what I did is apply a saturation note okay

you can find it in here saturation

and I reduce the saturation to zero

using the luminance math wreck 7:09

which means what I'm going to get after this saturation

is just the luminance of this image

according to the standard of the Rex 7:09

which is by the way

the same standard that is using the luminance key okay

so this is just creating the luminance map of my image

then what I'm doing here with this grade

is applying the same controls I have here

so this point that is now at 0 0

0 0 is the black point

this here on top is the white point

okay so what I did

is just use the black point and the white point

so I can set the amplitude of that luminance key

but in here

the difference on

for me is a massive difference

is you can study the decay of that mat

so you can move in here

and you can distribute

how you want that gamma to appear

the feather fall off

for instance to

to create a correlation with the roton out

okay so in here

if I apply that

you're gonna notice very

very tiny variation on how the grain is going to be

apply through the semi transparent areas

but even more

you can just play with the white and black point

and just to isolate that area and apply

way more or less grain in the areas of your interest

in this case

is not going to be that visible

but remember this

when you are going to have

quite contrast the areas in luminance terms okay

something to keep in mind

when you are creating a luminance key

is every time you are working with a mat

remember that you want

all your values to be normalized between 0 and 1

you don't want values below 0

so negative

or you don't want values to be super white above 1

so every time you're creating this luminance key

in a manual way

remember that in the great

you should take the black and the white clamp on okay

if you forget that

and then you increase the white point sometimes

you are going to increase your values beyond 1

and that is going to create funky effects in the Chemix

okay so just that to keep in mind

so this could be a good effect to apply

for the areas that are not in the alpha okay

but what if the proling is actually the alpha well here

what I did is just to apply a patch

and the patch is going to be perfectly grain

using the every grain

so the structure of the grain is perfectly done

but here you're gonna notice that

between this area of the grain

and this area of the grain

there is some kind of softening

here there is less grain than I expected

and this is because I'm mixing

the grain of the original plate

with the grain of my patch

and due to the graviations in here

that in here

around the center

is creating that blending effect

I show you before

with the averaging of the grains

so is actually contrasting each grain part

so when you are adding two grains

the result is less grain

so how to fix that

well let me show you in here a few ways of figuring out

because there is no one single way

depending on where are you applying the grain

or your personal taste

you're going to use one or another

so let's start by this setup

which is an special treatment of the fringe well

to understand this

you first need to understand

what's the fringe

the fringe represent in a mat

whatever is not white or black

so is increasing towards the center of the graviation

between the inside and the outside

okay so if I show you with an example

is going to be easier to visualize

so this is my shape

which is just a circle with a soft area

so in here the center of the circle

is going to be the heart part of the circle

in here the black is going to represent the outside

and if I apply a mask okay

just to apply a color correction

like in here

a grade to create this red

this is a regular mask okay

so what if I want to use the fringe of this mat

to apply the color correction

so this is the fringe in here

how I apply the fringe

well I went to the properties of the masking here

of the color correction

and you will find that this setup of the mask

and inject invert

and the fringe is available

and you can see here that is actually

using the pictures

that are not outside

not inside but in the middle

and the more you are going towards

the middle point of the gradient

the more strength is going to have

actually at the middle point

is going to be full

and then is going to decay towards the inside

and towards the outside

let me show you with the graphical representation

so if this is the ramp

as we saw in the slice

to remember in here

this is the normal ramp

so the middle point is in here

so in that middle point

the strength of the mask is going to be at full

so it's going to be here

let me put it in another color

so the strength is going to decay from the middle point

to the outside

and to the inside

so it's actually doing this

okay so is converting this linear ramp

to this kind of triangle

or pyramite okay

so in here is the maximum strength

this curve that I'm representing here

this triangle is called solarisation

okay so the solarization operation is actually

to take those values

and to create the maximum strength

towards the middle point

and then decay towards the 1 or the 0 values

okay so it's going to be easier

if I show you with a color look up

okay so this is my image

and this is the solarization operation

using a color look up

so a color look up

as you know

is just the curves

okay so this is a solarization

with the horizontal interpolation at the peak

which means just that at this point

and just using this softening for the decay

okay but I can change that

and use a more strict solarization

by using the linear interpolation

so this is an extreme solarization

okay so the middle point is the cane

in a linear fashion

towards 0 and towards 1

and you can see

the only part or portion of the image that is taking

is just what is not white or black

okay so this is the solarization

using a color look up okay

so if you want to create a solarization by yourself

is just as simple as taking

a color look up here

and just to go to the master or the alpha

depending on the channel you want

you create by pressing Alt and command in the centre

then in here

you modify the coordinates by manual inputs

and then the X must be the same

and in here the y

as I put it

the y must be 0 okay

and then in the middle

this must be point five

and the Y1 okay

and this is a soft solarize

if you want the strict solarized

you go to the interpolation linear

and that is the solarization okay

so you can create by yourself

and then you can decide

if you want more portions towards the outside

or more portions towards the inside

then you can play okay

so I find myself easier to work with the color look up

because sometimes you want to create a portion manually

or just reduce the other side

and in here you can do it graphically okay

by contrary

if you are using the automatic way

that is the only setup you have

okay so this is just for you

to let you know that you can modify that mask

whatever is going to work for your image

is going to be good

but at least you need to know how it works

okay so let's go back to the result image

because what I did in here

is quite similar to the previous example

but in this instance

I change the method

so what I did is

I'm going to apply the noise for everything

of course every time I'm applying a patch

I'm going to the noise

because I don't want to double the the grain

I'm going to apply my patch

and that patch is going to be pre

multiply by this shape

so in here I'm applying the alpha

and I'm going to pre multiply

then I'm going to put everything over okay

and then what I'm going to do is an extra pass of grain

and remember what I mentioned before about the sale

randomization of the values

what I mean is in here

I need to apply exactly the same grain

I'm applying to the original patch

I cannot apply another layer of grain

completely different

because that the result is going to lose more grain

that I'm going to add

so what I did is

I clone this grain

and this other grain

so the pattern and the randomization seat

that I'm getting from each

is exactly the same

so in here I have the same setup

that I got in the beginning

but the point that I'm adding in here is

I'm adding more grain to everything okay

and in here

and using the fringe

just to isolate that area that is

that is getting soft

and I'm adding that extra grain

so here have a look at difference

so I'm going to put in there

see that here

you can notice

it's not a massive difference in this case

but you will find that in some shots

this difference is going to be quite a lot

okay so with this

the nice thing is

I can play with the key mix

and going towards

a more grainy results

or reducing

to a natural

without any grain add

okay so in here

you can play a bit

I find that usually

the best result is around 0.25

because of course

you are getting already grain in there

and it's mixing with the original grain

so he's going to need kind of a

an extra quarter just

just for making the maths to work

okay but it's not a rule

so you will find that sometimes you need to add more

sometimes you need to add less

and at the end of the day

this is an eye by eye process okay

so in this case

we find a work around

to get the grain in those soft areas

let's have a look at another way

which is adding rain to the alpha

well in this case

probably this is not gonna work that much

because I'm going to find

like in here

that the patch is not perfectly

blend with the

softening effect

but this is just a good example

to let you know that

not all the techniques

are going to work the same

on all situations

so that's why I want you to know all of them

so you decide what to use in each case

okay so when you need it

what I did in here

is actually blend

the softening of my mat with differ

differ is again

a subtle randomization of frequencies in here

so it's just kind of grain that I create in mono

I means there is no randomization between the channels

because what I'm going to do

is just to apply it through the alpha

so the alpha is just one channel

so he's not going to make any difference actually

so remember that in the beginning

I was telling you about the frequencies

so the grain in here

the bigger is the grain

the less frequency you are going to get

in your grain pattern that you just created

the differ by default

is going to have a very high frequency

because it's randomizing from pixel to pixels

so if you apply a blur

you will see that the effect you are going to observe

is like the grain is actually being bigger

but actually

what you are doing is just creating clusters of pixels

so the effect is actually

that the grain is getting bigger

but you are actually just changing the frequencies

of that grain

okay so I create this grain plate okay

and what I did is to create it over a constant of 0.5

because that is going to allocate

all the randomizations

starting from the middle point of the image okay

so if I have a look at the slice tool

in that point

you will see that this is just constant image

and as soon as I start with that

see that is randomizing everything up and down

quite strongly

okay um in here

I reduce the

the frequency

but this is still the amplitude

is there okay

now with this roto

I'm applying an overly

and remember

that the overly is just adding the

differences from the 0.5

at we discuss in the class of the merge

so what I'm going to do is

I'm going to add the randomization of this grain

to the areas in here

not in the black

not in the white

but in the middle point

so this is the effect of the overlay

as you can see

that is creating a grainy area of decay

but is not perfectly white and black

so you are having some areas that you are getting

like a softness still

same with the dark

okay um that could be not noticeable

but I prefer just to use a mathematical approach

so if you don't want your grain to be notice

remember that you need to have a hard edge

so even if this is a grain

the grain should be hard

so what I did is

I called the roll of contrast

the roll of contrast is in here

and this is a note

where the contrast is going to be

treat as mathematical value

so is not like in the color correct

this contrast is actually in a perceptible level

okay so he's actually changing everything around 0.2

which is the center of the middle point

of the visual system in

in the eye I mean

but in here

you decide where is the center of your transformations

so in the center here

what I did is just to increase the contrast quite high

like a tree

and still even if it's not perfect

is going to work believe me

or if you want to increase more contrast

be my guest

and increase the number in here

the nice thing about the role of contrast

is keeping your values between 0 and 1

okay and in here

you can also change the distribution of that center

so you can go to a higher value or reduce

just to make everything really hard

okay so this could be understood

as the center of the solarization

so this is where is going to be your peak okay

so now that we have a hard edge for every grain

we can now copy to the original

and create the primal duplication

so see the difference now

okay so the difference is now mainly

that you are randomizing those soft areas

okay so when you apply that at the end

as you can see here on top

you're not going to see

where the grain is going to mix with the other

because it's actually not blending

it's actually grain on top of other grain okay um

this is the second process of adding grain

to the soft areas

you can go the other way around

and he's making your soft areas super hard

and then apply the grain to all the hard areas

and put everything on top

it's going to be easier if I show you here

so what I did is exactly the same patch okay

and in here I have exactly my same soft patch

what I'm doing is copying

prim multiplying

but what I did now is

okay in this case is going to be a bit silly

because I just can't take this

in my rotor and increase the feather fall off

but I'm doing this even for other cases

when you cannot just change the softening of your patch

so in that case

what I'm doing is mixing as I did before

but instead of mixing with the original

I'm going to mix with the V noise option

okay so now I have my patch without noise

be mixed with my original image without noise

so we are at the same level right now

um remember what I show you before

about the difference of the original

and the original with the effect

well now I'm going to show you another way of isolating

what is called the active area

with this representing

all the pixels change before and after a certain merge

so in here I have this merge operation

which is mixing the image without grain and the patch

so if you want to isolate all the pixels

that I am modifying

from my patch to the V noise option in here

you're going to use this combo of three nodes

which is the difference

which is representing

in every channel

everything that change

as you can see

there are pictures that are change more than others

and now what I'm doing is

I don't want to preserve the difference

for every channel

so for me every pixel that has change

is important as a whole

not for channels

so I'm going to reduce the saturation

but this time I'm going to use another luminance math

which is the maximum okay

the maximum is going to preserve for every channel

the maximum value

okay so now at the end

what I'm going to put is a grade in here

just for the alpha

which is the channel that I'm aiming for

and in there

what I put is the white point

to be at zero

that is going to create that

every pixel

that is not at zero

is going to be white

okay in here

as you can see

there is a certain kind of antialius okay

and that is normal

even in other cases

you will find that there are

areas of some kind of semi transparency

if I reduce

you will see that your image is now changing

so what I want is all my pixels to be

or white or black

nothing in the middle

okay so how

well you can use the gamma

and there is some number you can use in this gamma

which is in here one

with one two 3 4 5 six

7 and eight zeros

why eight zeros

you know it's because of the precision

of the 32 bit froaking point calculations within milk

the key Valentina decimal representation

of a step between

value of the 32 bit floating point

is around at 0.7 zeros of precision and one value

so that if we revert that effect using the gamma

if we put one with eight zeros

we are going to increase the gamma enough

just to cover all the steps in there

okay of course

if you use more

you are going to have the same result

if you have less probably

you are not going to have a quite visible result

but it's going to be the same there

okay so here you are

once you apply that

all your pixels are 0 or 1

let's look at the alpha

okay so I copied there

remember that we are working with a mat

so black clamp and white clamp

now we copy there

we apply the grain through everything okay

and now we pre multiply using that portion okay

then we merge everything together

and here you are

you are not going to get any step from the grain

and the patch

the proling with this method is

you are going to add areas

from the regional that has changed

let me show you with this area of action I created

this is quite similar to the isolation I did in here

for the difference

but in here

what I did is using a clamp okay

so if you use a clamp

and you enable everything

and you have values that are 0 or 1

so everything that is not 0

is going to be 1

okay so is another method of calculating the same thing

so you are changing all this area

and probably

the area you are

just aiming to change is the area of the eye

like in here

so I'm adding in here an area

that is being slightly soft

see

by the d noise

so this is the only inconvenient

I find when I'm using this method

okay it's very good

it's gonna work

it's going to be practically not noticeable

if well done

but it's gonna work very well

when you have a soft image

or your patch is mixing with a soft area

but as soon as you get any kind of detail in there

that detail is going to be slightly lost

okay so nothing major

but something to keep in mind

okay so this area of action we just discuss

could be a good way of interacting with the image

just to understand what areas of the image has changed

so for quality control or quality checks

you can understand

what areas of the image you actually change

if you are creating a rig removal

and then you find yourself that you are changing areas

that are not supposed to be changed

that is something to address

so in this area

everything is working fine

because I was changing the eye

and is just changing that area

and also those markers that were in

in there okay

so this is the difference from the regional

okay so this is a good companion of methodologies

to mixing the grain um

don't underestimate the grain

because it's a process that is quite complex

and even if you pay a lot of attention

to many aspects of the CG

um the integration and lighting and everything

but then your grain fails

everything is gonna fail

okay so I hope you find this class interesting

um that's all for this week

if you have any comments

questions or suggestions

please post them in the forums

and until next week

this has been Victor Perez for FX PhD

thanks for watching